| 摘要 |
PROBLEM TO BE SOLVED: To provide a driving device for a surface acoustic wave motor which can excite surface acoustic waves with power which is smaller than the conventional example by two or three digits, by returning the energy of acoustic waves propagated through a substrate without absorbing the energy at both end sections of the substrate. SOLUTION: A driving device is provided with unidirectional comb-shaped electrodes 4 and 5 which are not connected to external electrodes arranged on both sides of a surface acoustic wave element 1, but only perform electromechanical conversion, and comb-shaped electrodes 2 and 3 for energy supplement which are arranged between the electrodes 4 and 5 on both sides of the element 1 and connected to the external electrodes. The driving circuit can always maintain constant elastic oscillation, because the consumed power is supplied from the electrodes 2 and 3 by utilizing returned energy 7. |
